Results 21 to 30 of about 97,059 (278)
Invariant Subspaces, Quasi-invariant Subspaces, and Hankel Operators
Journal of Functional Analysis, 2001 The authors study algebraic properties of small Hankel operators on Bergman spaces of bounded symmetric domains \(\Omega\subset \mathbb{C}^n\). Here, the Bergman space \(L^2_a(\Omega)\) is the closed subspace of \(L^2(\Omega)\) consisting of analytic functions and the small Hankel operator \(\Gamma_\varphi\) with symbol \(\varphi\in L^2(\Omega)\) is ...
Guo, Kunyu, Zheng, Dechao
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Modeling Sampling in Tensor Products of Unitary Invariant Subspaces
Journal of Function Spaces, 2016 The use of unitary invariant subspaces of a Hilbert space H is nowadays a recognized fact in the treatment of sampling problems. Indeed, shift-invariant subspaces of L2(R) and also periodic extensions of finite signals are remarkable examples where this ...
Antonio G. García +2 more
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Journal of Inequalities and Applications, 2022 We provide upper bounds on the perturbation of invariant subspaces of normal matrices measured using a metric on the space of vector subspaces of C n $\mathbb{C}^{n}$ in terms of the spectrum of both unperturbed and perturbed matrices as well as the ...
Subhrajit Bhattacharya
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Isometries of ∗ -Invariant Subspaces [PDF]
Transactions of the American Mathematical Society, 1974 We consider families of increasing ∗ ^\ast -invariant subspaces of H 2 ( D ) {H^2}(D) , and from these we construct canonical isometrics from certain L 2 {L^2} spaces to
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An invariant subspace problem for multilinear operators on Banach spaces and algebras
Journal of Inequalities and Applications, 2016 This paper is concerned with the study of invariant subspace problems for nonlinear operators on Banach spaces/algebras. Our study reveals that one faces unprecedented challenges such as lack of vector space structure and unbounded spectral sets when ...
John Emenyu
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The invariant subspaces of S ⊕ S*
Concrete Operators, 2020 Using the tools of Sz.-Nagy–Foias theory of contractions, we describe in detail the invariant subspaces of the operator S ⊕ S*, where S is the unilateral shift on a Hilbert space. This answers a question of Câmara and Ross.
Timotin Dan
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Invariant Subspaces: An Alternative for Introducing Eigenvectors and Eigenvalues
Annales de Didactique et de Sciences Cognitives, 2023 The concepts of eigenvalue and eigenvector are typically approached algorithmically in introductory linear algebra courses. However, a more conceptual orientation involves connecting these notions to the concept of one-dimensional invariant subspace ...
Gisela Camacho, Asuman Oktaç
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Two-state intermittency near a symmetric interaction of saddle-node and Hopf bifurcations: a case study from dynamo theory [PDF]
, 2003 We consider a model of a Hopf bifurcation interacting as a codimension 2 bifurcation with a saddle-node on a limit cycle, motivated by a low-order model for magnetic activity in a stellar dynamo.
Alastair M. Rucklidge +24 more
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Proper contractions and invariant subspaces
International Journal of Mathematics and Mathematical Sciences, 2001 Let T be a contraction and A the strong limit of {T∗nTn}n≥1. We prove the following theorem: if a hyponormal contraction T does not have a nontrivial invariant subspace, then T is either a proper contraction of class 𝒞00 or a nonstrict proper contraction
C. S. Kubrusly, N. Levan
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Constrained characteristic functions, multivariable interpolation, and invariant subspaces
Journal of Inequalities and Applications, 2020 In this paper, we present a functional model theorem for completely non-coisometric n-tuples of operators in the noncommutative variety V f , φ , I ( H ) $\mathcal{V}_{f,\varphi,\mathcal{I}}(\mathcal{H})$ in terms of constrained characteristic functions.
Jian Hu, Maofa Wang, Wei Wang
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